netfilter: nft_inner: Fix IPv6 inner_thoff desync (Linux Linux)

CVE-2026-46244
CRITICAL 9.1

At a glance

Source
NVD
EPSS
EPSS 0.42 % · percentile 36 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_inner: Fix IPv6 inner_thoff desync In nft_inner_parse_l2l3(), when processing inner IPv6 packets, ipv6_find_hdr() correctly computes the transport header offset traversing all extension headers, but the result is immediately overwritten with nhoff + sizeof(_ip6h) (40 bytes), which only accounts for the IPv6 base header. This creates a desync between inner_thoff (wrong — points to extension header start) and l4proto (correct — e.g., IPPROTO_TCP), enabling transport header forgery and potential firewall bypass. This issue affects stable versions from Linux 6.2. For comparison, the normal (non-inner) IPv6 path correctly preserves ipv6_find_hdr()'s result. Removing the incorrect overwrite ensures that ipv6_find_hdr()'s calculated transport header offset is preserved, thereby fixing the desynchronization.

Weaknesses (CWE)

  • CWE-823 — Use of Out-of-range Pointer Offset
  • CWE-682 — Incorrect Calculation

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NLinux
CVSS 3.1HIGH 7.3CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:Hredhat-SADP
CVSS 3.1CRITICAL 9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)
CVSS 3.1HIGH 7.3CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:HNVD · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected 3a07327d10a09379315c844c63f27941f5081e0a < c161ad9157f5a0429b5ff94d9770faf3bf48d273 ; affected 3a07327d10a09379315c844c63f27941f5081e0a < 870d59e2cf218e7418491e26bad768cb16654582 ; affected 3a07327d10a09379315c844c63f27941f5081e0a < 689bbf48c1f45130086ae1c46ab83ea4c753c601 ; affected 3a07327d10a09379315c844c63f27941f5081e0a < d0f98a3617f6ae5b1e95cde1e68e7ead4a1279ce ; affected 3a07327d10a09379315c844c63f27941f5081e0a < b6a91f68ebfed9c38e0e9150f58a9b85da07181c
Linux · Linuxaffected 6.2 ; unaffected 0 < 6.2 ; unaffected 6.6.142 ≤ 6.6.* ; unaffected 6.12.92 ≤ 6.12.* ; unaffected 6.18.34 ≤ 6.18.* ; unaffected 7.0.11 ≤ 7.0.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD